1. Field of the Invention
The present invention relates to a hermetic type compressor, and more particularly to a suction muffler for a hermetic type compressor having an improved structure to reduce the noise transmitted by the compressor during operation.
2. Description of the Related Art
As shown in FIG. 1, a compressor 10 typically used in home appliances, such as refrigerators, includes an outer casing 20 defining a sealed interior space therein, a body 30 received in the outer casing 20 and having a cylinder 50 for compressing a refrigerant, and a suction muffler 40 for reducing noise generated during operation of the compressor.
As shown in FIG. 2, the suction muffler 40 includes a muffler body 41 and refrigerant suction pipe 42. The muffler body 41 is disposed above the cylinder 50 and has a refrigerant supply port 41b, which communicates with a refrigerant supply pipe 21. The refrigerant suction pipe 42 connects the interior of the muffler body 41 with a cylinder head portion 51.
In the suction muffler 40 constructed as above, refrigerant flows into the compressor 10 via the refrigerant supply pipe 21, and into a resonance chamber 41 a defined in the muffler body 41 via the refrigerant supply port 41b. The refrigerant then flows into the cylinder head portion 51 via the refrigerant suction pipe 42. The path of the refrigerant from the refrigerant supply pipe 21 to the cylinder head portion 51 is indicated by a solid-line arrow of FIG. 2. From the cylinder head portion 51, the refrigerant flows to a cylinder inlet 52 and into an interior of the cylinder 50, where the refrigerant is compressed to high pressure.
As the refrigerant flows through the inlet 52 and an outlet 53 of the cylinder head portion 51, valves (not shown) in the cylinder head portion 51 open and close, producing vibration and noise. The noise exits from the cylinder head portion 51 through the muffler body 41 and the refrigerant supply pipe 21. The path along, which the noise travels, is a reverse of the path of the refrigerant and is indicated by a dotted-line arrow of FIG. 2.
In order to minimize the level of noise from the muffler 40, a noise transmission path within the resonance chamber 41a should be as long as possible. Accordingly, the refrigerant suction pipe 42 extends from the bottom of the resonance chamber 41a to a predetermined height corresponding to an upper portion of the muffler body 41.
The extended length of the refrigerant suction pipe 42, however, increases a flow resistance for the refrigerant flowing through the muffler 40. Accordingly, the compressing efficiency of the compressor 10 is adversely affected. If the refrigerant suction pipe 42 is shortened, however, then the noise transmission path is also shortened, and accordingly, the compressor 10 will transmit a higher level of noise.
Albeit not shown, the muffler 40 may further include a baffle to reduce the level of noise produced by the compressor 10. Alternatively, the resonance chamber 41a of the muffler 40 may have a dual chamber structure. These approaches, however, have several disadvantages, such as complicating the manufacturing process, decreasing productivity, and increasing manufacturing costs.
The present invention has been made to overcome the above-mentioned problems of the related art, and accordingly, it is an object of the present invention to provide a suction muffler for a compressor having a refrigerant suction pipe and a resonance chamber of an improved structure to reduce the level of noise produced by the compressor.
The above object is accomplished by a suction muffler for a compressor according to the present invention, including a muffler body, a refrigerant suction pipe, and a noise reducing means. The muffler body defines a resonance chamber, which communicates with the refrigerant supply pipe of the compressor. The refrigerant suction pipe for connecting the resonance chamber to a cylinder head portion of the compressor. The noise reducing means is formed in the resonance chamber and reduces the noise that is created by the discharge of refrigerant. The noise reducing means accomplishes this by defining a noise transmission path, through which the noise is transmitted from the cylinder head during the refrigerant discharge, that is separate from a refrigerant flow path, through which a refrigerant flows into the cylinder head portion.
The noise reducing means includes a hole formed in a portion of a cylindrical wall of the refrigerant suction pipe. The hole permits a refrigerant to flow therethrough.
The cylindrical wall of the refrigerant suction pipe may also include a pair of holes formed therein, the holes being located opposite one another.
Further, the noise reducing means includes a guiding portion to direct the refrigerant from the refrigerant supply pipe into the hole, and also to block the diffusion of noise and to direct the noise in a particular direction about the resonance chamber.
The guiding portion includes a portion of the muffler body that is indented toward the refrigerant suction pipe.